Effectiveness of digital health interventions on blood pressure control, lifestyle behaviours and adherence to medication in patients with hypertension in low-income and middle-income countries: a systematic review and meta-analysis of randomised controlled trials

Figures

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  Fig. 1. PRISMA flow chart of study selection. PRISMA flow diagram specifying the considerations to exclude and include the articles.

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  Fig. 2. Forest plot of the mean difference in SBP between the intervention and control groups. Forest plot of mean difference in systolic blood pressure (SBP) (expressed as mm Hg) between the digital health intervention and the control groups, and subgroup analysis by mode of delivery of the intervention (Mobile phone call, Short message service (SMS) and Smartphone app). The size of the blue squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) crossing zero (vertical line) are inconclusive. Studies with more participants have narrower CIs. The red diamonds represent the summary effect sizes in each of the subgroups and the green the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction in SBP is seen in the intervention group, compared with the control group in the overall sample and with the two modes of delivery (SMS and smartphone app). SMS interventions displayed the greatest reduction, compared with smartphone apps and mobile phone calls, but the differences between the three modes were not significant. The data present high heterogeneity.

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  Fig. 3. Meta-analysis of dichotomous outcome measurements for BP control. Forest plot of odds ratio in blood pressure (BP) control between the digital health intervention and the control groups. The size of the blue squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) crossing zero (vertical line) are inconclusive. Studies with more participants have narrower CIs. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction in BP is seen in the intervention group, compared with the control group. The data present high heterogeneity.

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  Fig. 4. Meta-analysis of continuous outcome measurements for low-salt diets. Forest plot of standard mean difference for low-salt diets between the digital health intervention and the control groups. The size of the green squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) are inconclusive. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction for low-salt diets is seen in the intervention group, compared with the control group. The data present high heterogeneity.

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  Fig. 5. Meta-analysis of continuous outcome measurements for PA. Forest plot of standard mean difference for physical activity (PA) between the digital health intervention and the control groups. The size of the green squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) crossing zero (vertical line) are inconclusive. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction for PA is seen in the intervention group, compared with the control group. The data present high heterogeneity.

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  Fig. 6. Meta-analysis of dichotomous outcome measurements for smoking reduction. Forest plot of risk difference for smoking reduction between the digital health intervention and the control groups. The size of the blue squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) crossing zero (vertical line) are inconclusive. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction in smoking reduction is seen in the intervention group, compared with the control group. The data present no heterogeneity.

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  Fig. 7. Meta-analysis of continuous outcome measurements for adherence to medication. Forest plot of standard mean difference for continuous outcome measurements for adherence to medication between the digital health intervention and the control groups. The size of the green squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) crossing zero (vertical line) are inconclusive. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction in adherence to medication is seen in the intervention group, compared with the control group. The data present high heterogeneity.

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  Fig. 8. Meta-analysis of dichotomous outcome measurements for adherence to medication. Forest plot of standard mean difference for dichotomous outcome measurements for adherence to medication between the digital health intervention and the control groups. The size of the blue squares indicates the weight of the evidence from each of the studies. Studies with CI (horizontal line) are inconclusive. The black diamonds represent the summary effect sizes in the overall sample, with the width of the diamond indicating the 95% CI. A statistically significant greater reduction in adherence to medication is seen in the intervention group, compared with the control group. The data present moderate heterogeneity.